摘要
研究了2种饱水轻细骨料(粉煤灰陶砂和页岩陶砂)各自等体积取代不同普通砂时对水灰比0.3和0.4混凝土28d抗压强度影响。试验表明:取代砂体积为0-60%时,随着轻细骨料掺量增加,水灰比0_3两种轻细骨料混凝土28d抗压强度都高于普通混凝土,且都在40%时达到最高;取代砂体积0-40%时,水灰比0.4两种轻细骨料混凝土28d抗压强度随轻骨料掺量增加而减小。当水灰比和取代砂体积相同时,掺粉煤灰陶砂混凝土28d抗压强度都要高于掺页岩陶砂混凝土。对含有轻细骨料混凝土的抗压强度进行理论模拟,为此提出了混凝土中轻骨料体积-孔隙率转换系数.γ(0.1),结合强度孔隙率模型、Powers模型和内养护浆体模型计算了轻细骨料内养护混凝土28d抗压强度,模拟结果与试验值较为吻合。
Two types of saturated lightweight fine aggregates (blast furnace slag and shale sand) were used to substitute the equivalent volume of regular fine aggregates in the concrete specimens(with W/C ratio of 0.3 and 0.4 ).The influence on 28 d compressive strength due to the replacement of regular fine aggregates by these lightweight fine aggregates was investigated.Experimental evidence showed that when there was 0-60% volume of fine aggregate replaced, at 0.3 W/C ratio ,the concrete samples with lightweight fine aggregates would exhibit higher 28 d compressive strength than normal concrete.When 0-40% of fine aggregate was substituted by lightweight fine aggregates, for W/C=0.4, the specimens' 28 d compressive strength decreases as the proportion of fine aggregate increases.When the volume fraction of the replacement fine aggregate and the W/C were equal,the blast-furnace-slag-blend concrete specimens were stronger in compressive than their shale counterparts.It attempted to model the compressive strength of lightweight-fine-aggregate concrete.A parameter- lightweight fine aggregate volume-to-porosity conversion coefficient γ(0-1) was introduced.The Strength-porosity relationship,Powers model, internal curing paste volume model were incorporated in this model prediction of the 28 d compressive strength of the specimens. The test results and the model predictions have shown good agreement.
出处
《混凝土》
CAS
CSCD
北大核心
2013年第3期44-47,51,共5页
Concrete
基金
高等学校博士学科点专项科研基金资助课题(20110002120010)
关键词
轻细骨料
混凝土
内养护
抗压强度模拟
lightweight fine aggregate
concrete
internal curing
prediction of compressive strength